On the Nature of the Unique Hα-emitting T Dwarf 2MASS J12373919+6526148

  title={On the Nature of the Unique H$\alpha$-emitting T Dwarf 2MASS J12373919+6526148},
  author={James William Liebert and Adam J. Burgasser},
  journal={The Astrophysical Journal},
We explore and discount the hypothesis that the strong, continual H?-emitting T dwarf 2MASS J12373919+6526148 can be explained as a young, low-gravity, very low mass brown dwarf. The source is already known to have a marginally fainter absolute magnitude than similar T dwarfs with trigonometric parallax measurements and has a tangential velocity consistent with old disk kinematics. Applying the technique of Burgasser et al. on new near-infrared spectroscopy for this source, estimates of its… 

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